Synthesis of cis and trans Whisky and Cognac Lactones by the Regiocontrolled Alkylation of 2-(Trimethylsiloxy)furan

Article abstract of DOI:10.1002/hlca.19890720625

The racemic cis- and trans-5-butyltetrahydro-4-methylfuran-2-ones ( = whisky lactones) and their higher homologues tetrahydro-4-methyl-5-pentylfuran-2-ones ( = cognac lactones) have been prepared in 2-3 steps from 2(trimethylsiloxy)furan.Regioselective alkylation of the latter afforded the 5-butyl- and 5-pentylfuran-2(5H)-ones which served as precursors for the stereocontrolled construction of either diastereoisomer of the beverage lactones.The structure and tautomerization of the diazomethane adducts of these 5-alkylfuran-2(5H)-ones are also described.